Grinding wheel feed for grinding machines



Dec. 20, 1955 R. s. PYNE ET AL 2,7 7,339

GRINDING WHEEL- FEED FOR GRINDING MACHINES Filed Jan. 14, 1954 4 Sheets-Sheet l INVENTORS. ROGER S. PYNE AND RICHARD M. ANDERSON A TTOPNE Y5 Dec. 20, 1955 R. s. PYNE ET AL GRINDING WHEEL FEED FOR GRINDING MACHINES 4 Sheets-Sheet 2 Filed Jan. 14, 1954 ll Hll INVEN I URS ROGER S. PYNE Ann RBIHARD "LANDERSON VT 21 VA A 7 TOP/VL K9.

Dec. 20, 1955 R. s. PYNE ET AL GRINDING WHEEL FEED FOR GRINDING MACHINES 4 Sheets-Sheet 3 Filed Jan. 14, 1954 :III II ROGER s INVENTORS PYNE m RICHARD M. ANDERSON A T TOPNL'YS' Dec. 20, 1955 R. PYNE ET AL GRINDING WHEEL FEED FOR GRINDING MACHINES 4 Sheets-Sheet 4 Filed Jan. 14, 1954 lNVfA/TORS. PYNE AND NDERSON United States Patent Ofiice 2,727,339 Patented Dec. 20, 1955 GRINDING WHEEL FEED FGR GRINDKNG MACHINES Application January 14, 1954, Serial N 4%,956 Claims. (Cl. 51165) M. Anderson,

This invention relates to improvements in the mechanism by which the grinding wheel of a grinding machine, such as a cylindrical grinder, is fed toward the work.

In: grinding machines of the type to which the invention isdirected the grinding wheel is mounted on a support or slide which is moved toward and from the work by a feed screw engaged in a nut fixed to'the slide, the work being reciprocated' across the grinding periphery of the wheel by a table carrying the usual head and foot stocks by which the work is supported and rotated. At the end of each traverse the grinding wheel is automatically advanced or fed toward the work piece.

It is the generalobjeet of the present invention to provide improved'mcans for automatically feeding the grinding wheel toward the work.

More specificobjects are to provide a wheel feed permitting exceedingly small increments of feed and a fine adjustment of the feeding increments, operable while the machine is running.

A.,further. object is to provide means by which the automatic feeding means may be automatically released andmanual feeding means established as the end of the grinding operation approaches, or manually released at any time to establish manual feed.

Another object is to provide a quick manual forward and back feed, operable at any time to move the wheel from the work and return it to that grinding position attained at the time by the operation of the automatic or normal manual feeding mechanism.

Another object is to provide a table traverse actuating mechanism so associated with the feed actuator as to simultaneously initiate both the reversing of the table traverse and the forward feeding of the wheel in timed relation andin a manner consistent with actuation of both from a lever movable in opposite directions from a neutral position.

Other and further objects and advantages will be made apparent from the disclosures of the accompanying drawings-and of the following specification and claims.

Itv is an object of the present invention to provide a finer feed of the wheel toward the work, and improved reversal of the traverse movement and a quicker return of: the wheel to initial feed position than is afiorded by present construction.- Other and further objects and advantages will be made apparent from the disclosure of the accompanying drawings and in the following specification and claims.

In the drawings,

Fig. 1 is a front elevational view of a grinding. machine embodying the invention, parts being omitted;

Fig. 2 is a front elevational view of the wheel feeding mechanism on a larger scale, parts being broken away;

Fig. 3 is a sectional view substantially on line 33 of Fig. 2;

Fig. 4 is a rear elevational view or" the structure of Fig. 2' showing the traverse reversing mechanism, other parts being omitted;

Fig. 5 is a detail sectional view substantially on line 5-5 of Fig; 2, and

Fig. 6-is a fragmentary view of parts as shown in Fig. 4 but in a different position.

Referring to Fig. l of the drawing the frame, of the machine is generally indicated at 1. The frame 1 reciprocably supports a table 2 which carries the usual head and foot stocks 3 and 4 in which the work piece is mounted. Table 2 is reciprocated, by means not shown, to traverse the work pieceback and forth with respect to the grinding wheel indicated at 5. The direction of movement of the table 2 is automatically reversedat the end of each traverse by theengagement of spaced dogs 6, adjustably fixed to thecarriage, with a reversing lever 7 m me manner usual to this type of machine. The. grinding wheel 5, driven by any suitable means is mounted'on the usual slide, not shown, which is moved toward and from the work by the usual feed screw indicated at 8, Fig. 3.

The parts above referred to are those comprising and found in conventional cylindrical grinding machines and with exceptions later noted may be of, usual or desired construction.

The present invention relates to the drive. and control of feed screw 8 and the related elements, said drive and control mechanism being mounted in a housing 9"fixed to the frame 1, Fig. 1.

As best shown in Fig. 3 the, feed screw 8 is formed on a .shaft'ltl, the outer end of which is journaled in a ball bearing ll. Outwardly of bearing 11 the shaft 10' carries, a gear 12 splined thereto and meshing with a gear 13 formed on or fixed to a shaft 14. Agear 15 ismounted on shaft 14 by means of a one way, or over-running clutch 16 which engages and drives shaft 14 when the gear 15 is driven in a counterclockwise direction, as viewed in Fig. 2, thus driving feed screw 8 to feed the. grinding wheel toward the work.

A rack 17 is pivotally connected, as at 18, to one arm. 19 of a bell crank 20 which is pivoted at 21 to housing9. A spring 22 normally maintains rack 17 in meshwith gear 15. One arm of the bell crank, preferably arm.19, is formed with an abutment 23 which is normally held by a spring 24 in engagement with an adjustable stop. member 25 in the form of.a disc eccentri'cally securedon. a shaft 26.

The other arm 27 of hell crank 29, engages the, lower end of a plunger 28 slidable in. a bracket, 29 carried by. housing 9. Theupper end of plunger 28 carries a head. 30. A rocker, 31, fixedto the shaft 32 to which reversing lever 7 is secured carries spaced rolls 33 adapted to: engage the upper face of the head 30 when lever 7 is.v engaged by one or the other of dogs 6 to reversezthe traverse of the table 2.

As shown in Pig. 2 when lever 7 is engaged by the dog; 6 (the left hand dog as viewed in Fig. 1), the lever.- isv rocked from its normal position A to the position B. As the lever 7 moves to position B one of the rolls 33 engages and depresses plunger 28, against the action of a spring 35 which surrounds the plunger 28 between head, 30. andbracket 29. The downward movement of plunger 28. brings the lower end of the plunger into contact with arm 27 of hell crank 20 and rocking thelatter counterclock-- wise, as viewed in Fig. 2, against theaction of, spring 24- and moving rack 17 to the left thus driving gear 15 andthe feed screw 8 toadvance the wheel a. predetermined distance toward the work piece. The movement of lever 7 reverses the direction of the table traverse,.as later dc.- scribed, and as dog 6 retreats from lever 7 the. latter is. restored to normal positionA by the upward movement. of plunger 28'under the action of spring 35. As plunger 28 moves upwardly away from arm 27 spring 24 swings the bell crank clockwise to bring abutment 23 against stop 25, rack 17 moving to the right and driving gear 15 clockwise but without driving shaft 14 due to the one way clutch 16. Preferably an adjustable stop 36 is provided for the forward movement of arm 19. As will be apparent the extent of movement of rack 17 at each actuation and therefore the extent of the feed imparted to the grinding wheel by feed screw 8 is controlled by the setting of eccentric stop 25. Preferably shaft 26 which carries stop is provided with a graduated dial knob 37 by which the stop may be set to effect the desired feed. As will be apparent this setting may be made or changed while the machine is in operation and that an extremely fine control of the extent of feed is afforded. it will further be apparent that when lever 7 is swung to the position C by the second dog 6 to initiate the return traverse of the table 2 the actuation of the feed screw is repeated.

When complete automatic operation, which provides automatic size control is not desired in a given grinding operation then, in the final stage, feed of the grinding wheel may be manually controlled by the operator since, as this stage is reached, the automatic feed above described is automatically released.

For this purpose and the purposes of manual feed generally a hand wheel 40 provided with a handle 41 is releasably locked on the outer end of shaft 14. Hand wheel 48 carries a rearwardly extending stop pin 42. As the grinding process continues shaft 14 is being rotated counterclockwise a few degrees at each reciprocation of the table 2, carrying pin 42 with it. As the end of the operation approaches, the pin 42 engages the inclined edge 43 of a slide 44. Slide 44- is provided with rack teeth 45 which engage a pinion 46 formed on a stub shaft 47 provided with a handle 48. Pinion 46 also meshes with a rack 50, the upper end of which is positioned below but in engageable relation with the free end of rack 17. Continued rotation of hand wheel 40 through the successive operations of rack 17 brings pin 42 into engagement with inclined face 43 of slide 44 forcing the latter outwardly thereby rotating pinion 46 and raising rack 58 to lift rack 17 out of engagement with driving gear 15, thus discontinuing further driving of feed screw 8 by the rack 17 even though the latter continues its intermittent movement as lever 7 is alternately engaged by the dogs 6. The length of inclined face 43 is such that after rack 17 has been lifted clear of gear 15 the operator can manually feed the grinding wheel forward a predetermined distance, usually in the range of seven ten thousandths of an inch, by rotation of hand wheel 40. At the end of this manual feed, pin 42 engages in a stop seat 51, formed in member 44 at the upper end of inclined surface 43, restraining the hand wheel against further feeding movement. In this position a ball detent 52 (Fig. 5), under the action of spring 53 engages in a socket 54 formed in slide 44 releasably holding the latter in its feed restraining position. To cornmence a second operation the hand wheel 40 may be rotated clockwise to reversely feed the grinding wheel to its initial position and returning pin 42 to its original position, slide 44 being returned to lowered position by means of handle 48 thus reengaging rack 17 with gear 15.

For full freedom of manual. operation of the feed screw, forward and back, by the hand wheel the slide 44 may be completely retracted by handle 48 until detent 52 seats in a second'socket 55 holding the seat 51 clear of the path of pin 42, with rack 17 held out of mesh with gear 15.

A limited rapid feed movement is provided, which is operative in any position of the grinding wheel and during operation of the machine. As shown in Figs. 3 and 4 shaft 10, carrying feed screw 8, with its bearing 11 and gear 12 are axially locked in a cartridge 68 slidably mounted in a bore 61 formed in the housing 9. As cartridge is moved in the housing it carries shaft it), screw 8 and the slide upon which the grinding wheel is mounted, together with hearing 11 and gear 12, with it. The stroke of cartridge 60 in the housing is limited by the engagement of flange 62 of the cartridge with one end face 63 of the bore 61 and the engagement of gear 12 with the other end face 64 of the bore the permitted stroke of the bore being preferably of the order of /4 of an inch. The gear 13 is of sufficient length to maintain a driving engagement with gear 12 throughout the stroke of the cartridge 60. In Fig. 3 the parts are shown in fully advanced position.

Cartridge 68 is formed with a circumferential groove 65 in which opposed bronze shoes 66 (Fig. 4) engage. The shoes are pivoted on arms 67 of a yoke 68 which is pivoted on trunnion 69. The yoke 68 is pivoted about a trunnion 69, to slide cartridge 60 in its bore, by spaced eccentric cams 7i) fixed to a shaft 71 and engaging bearing pieces 72 on opposite sides of the yoke. Shaft 71 is provided at its outer end with an operating lever handle 73. Adjustable stop members 75, secured to shaft 71 are adapted to engage opposite sides of web 76 extending from housing 9 to limit rotative movement of shaft 71 to an oscillation within the effective throw of the cams 70.

Assuming the parts are in the position of Fig. 3, it will be apparent that, regardless of the position to which the grinding wheel and its slide have been advanced along feed screw 8 by the automatic, intermittent actuation of rack 17, or by manual operation through hand wheel 40, the grinding wheel together with its slide and its feed screw 8 may be quickly retracted by means of lever 73 to the extent of the permitted sliding movement of cartridge 69 in its bore. Thus the grinding wheel may be quickly retracted during a grinding operation for inspection of the work or other purposes and may be equally quickly returned to its grinding position. In general the structure just described gives a quick manual grinding wheel feed alternative to the slow manual feed through hand wheel 40.

As above described rack 17 is actuated to impart an increment of feeding movement to screw 8 as the lever 7 is moved from position A to either position B or C (Fig. 2) by one or the other of the spaced dogs 6. The movement of lever 7 by dogs 6 also actuates the means which reverses the direction of movement of the table 2.

As shown in Figs. 3 and 4, shaft 32, to which lever 7 is fixed, extends rearwardly of housing 9, and the end of shaft 32, opposite lever 7 is provided with an arm 80 which is provided with a pin 81 which rides in a slot 82 formed in a cam block 83. One face of block 83 carries a wedge shaped cam 84 which ,moves across a roller 85 carried by one end of a lever 86 pivoted intermediate its ends at 87. The roll 85 is urged toward the cam 84 by a spring 88. As the lever 7 is engaged and moved from its vertical position by one of the dogs 6, as shown in Fig. 4, the pin 81 engages an end of slot 82 and moves block 83 until the high point of cam 84 is just beyond the center of roll 85 when the action of spring 88 snaps the block the rest of the way in the direction in which it was moving as shown in Fig. 6, so that, as shown in the latter figure the pin 81 engages the opposite end of slot 82 when lever 7 returns to its vertical neutral position as the dog 6 moves away from it. The pin 81 is thus in position to move the block 83 in the opposite direction for actuation by roll 85 and cam 84 when lever 7 is moved from position A to position C by the second dog 6. Block 83 is connected by any suitable linkage, not shown, to the conventional reversing clutches, not shown, through which the table 2 is driven in the usual manner.

What is claimed is:

i. In a grinding machine having a reciprocating work supporting table having spaced dogs for reversing the movement of the table, a slide for supporting a grinding wheel and a screw shaft for feeding said slide toward and from the work; means for driving said screw shaft a predetermined distance on each reversal of the movement of the table which comprises a gear mounted in driving relation on the screw shaft, a stub shaft, a second gear fixed to said stub shaft and mesh ng with said first gear,

a third gear mounted on said stub shaft, a rack engaging said third gear, means actuated by engagement with said dogs to impart a forward and reverse stroke to said rack, and a one way clutch connecting said third gear to the stub shaft to drive the stub shaft in a direction to advance the grinding wheel supporting slide in the direction of the work.

2. In a grinding machine having a reciprocating work supporting table having spaced dogs for reversing the movement of the table, a slide for supporting a grinding wheel and a screw shaft for feeding said slide toward and from the work; means for driving said screw shaft a predetermined distance on each reversal of the movement of the table which comprises a gear mounted in driving relation on the screw shaft, a stub shaft, a second gear fixed to said stub shaft and meshing with said first gear, a third gear mounted on said stub shaft, a rack engaging said third gear, a pivoted lever, having a free end pivotally connected to said rack, means engageable with said lever and actuated by said dogs to oscillate said lever and impart a forward and reverse stroke to said rack and a one way clutch connecting said third gear to the stub shaft to drive the stub shaft in a direction to advance the grinding wheel supporting slide in the direction of the work upon one of said strokes of the rack.

3. In a grinding machine having a reciprocating work supporting table having spaced dogs for reversing the movement of the table, a slide for supporting a grinding wheel and a screw shaft for feeding said slide toward and from the work; means for driving said screw shaft a predetermined distance on each reversal of the movement of the table which comprises a gear mounted in driving relation on the screw shaft, a stub shaft, a second gear fixed to said stub shaft and meshing with said first gear, a third gear mounted on said stub shaft, a rack engaging said third gear, a pivoted lever, having a free end pivotally connected to said rack, means engageable with said lever and actuated by said dogs to oscillate said lever and impart a forward and reverse stroke to said rack, a one way clutch connecting said third gear to the stub shaft to drive the stub shaft in a direction to advance the grinding wheel supporting slide in the direction of the work upon one of said strokes of the rack, and means to adjust the length of stroke imparted to the rack by said lever.

4. In a grinding machine having a reciprocating work supporting table having spaced dogs for reversing the movement of the table, a slide for supporting a grinding wheel and a screw shaft for feeding said slide toward and from the work; means for driving said screw shaft a predetermined distance on each reversal of the movement of the table which comprises a gear mounted in driving relation on the screw shaft, a stub shaft, a sec- 0nd gear fixed to said stub shaft and meshing with said first gear, a third gear mounted on said stub shaft, a rack engaging said third gear, a bell crank having one arm pivotally connected to said rack, spaced stops engaging opposite sides of said arm, one of said stops being adjustable, a spring normally holding said arrn against the adjustable stop, means engaging the other arm of the bell crank and actuated by said dogs to move said first arm from said adjustable stop and against the other stop, said last named means and spring oscillating said first arm to impart a forward and reverse stroke to said rack and a one way clutch connecting said third gear to the stub shaft to drive the stub shaft in a direction to advance the grinding wheel supporting slide in the direction of the work upon one of said strokes of the rack.

5. In the combination of claim 1, means to manually rotate said stub shaft, means to raise said rack out of mesh with said third gear and means carried by said stub shaft to actuate said rack raising means at a predetermined position of rotation of said stub shaft.

6. In a grinding machine having a reciprocating work supporting table having spaced dogs for reversing the movement of the table, a slide for supporting a grinding wheel and a screw shaft for feeding said slide toward and from the work; means for driving said screw shaft a predetermined distance on each reversal of the movement of the table which comprises a gear mounted in driving relation on the screw shaft, a stub shaft, a second gear fixed to said stub shaft and meshing with said first gear, a third gear mounted on said stub shaft, a rack engaging said third gear, a rock shaft, an arm carried by said rock shaft and engageable with said dogs to rock said rock shaft, means carried by said rock shaft to efiect reversal of the table movement, and means carried by said rock shaft to impart a forward and reverse stroke to said rack upon each table reversing movement of said rock shaft, and a one way clutch connecting said third gear to said stub shaft to drive the stub shaft in a direction to advance the grinding wheel supporting slide in the direction of the work.

7. In the combination of claim 1 means to raise said rack out of mesh with said third gear, means driven by said stub shaft to actuate said rack raising means at a predetermined position of rotation of said stub shaft, and manually operated means to actuate said rack raising means independently of said means driven by the stub shaft.

3. In the combination of claim 1 a reciprocable member engageable with said rack to raise the latter from mesh with said third gear, rack teeth formed on said reciprocable member, a pinion engaging said rack teeth, and means to rotate said pinion to reciprocate said reciprocable member and thereby raise said rack from mesh with said third gear.

9. In the combination of claim 8 a second reciprocable member having rack teeth engaging said pinion and provided at one end with a cam surface, and means carried by said stub shaft and engageable with said cam surface in a predetermined position of rotation of said stub shaft to drive said second reciprocable member to rotate said pinion and thereby drive said first reciprocable member to raise said rack out of mesh with said third gear.

10. The combination of claim 1 in which said screw shaft with said first gear are mounted for axial reciprocation, stop means to limit the range of said axial reciprocation, said first and second gears having a Width of mesh to maintain meshing engagement through the range of said axial reciprocation, and means to axially reciprocate said screw shaft Within the range determined by said stop means.

References Cited in the file of this patent UNITED STATES PATENTS 1,015,567 Landis Jan. 23, 1912 1,104,988 Hanson July 28, 1914 1,121,773 Spence Dec. 22, 1914 2,021,066 Huxford et al. Nov. 12, 1935 2,240,506 Levesque et al. May 6, 1941 2,312,161 Hartman Feb. 23, 1943 2,340,096 Woodbury et al. Jan. 25, 1944 2,378,903 Baldenhofer June 26, 1945 2,657,505 Price Nov. 3, 1953 

